If you are wasting your exotic slot for knucklehead in POE then your a complete knucklehead. Celestial Nighthawk.....Symb.....the new exotic arms or don't touch me (depending on that rounds perks)....crest of alpha lupi......new exotic boots......all of those are far superior options to the knucklehead perk. Unless you run around always ADSing. Knucklehead is really only good for PVP and even then its a pretty meh exotic....it would be better if it gave radar on all of your weapons.